Pendent incandescent electric light



(No Moaif) y W. A. JOHNSTON 8v J. O. DAVIDSON.

PENDENT INGANDESOENT ELE'GTRIO LIGHT.

No. 504,475. Patented Sept. 5, 1893.

UNITED STATES PATENT OFFICE.

WILLIAM A. JOHNSTON AND JOHN C. DAVIDSON, OF PRINCES BAY, NEW

YORK, ASSIGNORS TO THE S. S. WHITE DENTAL MANUFACTURING COM- PANY, OF'PHILADELPHIA, PENNSYLVANIA.

PENDENT IN CANDES CENT ELECTRIC LIGHT.

SPECIFICATION forming part of Letters Patent No. 504,475, dated September 5, 1893.

' Application filed April 28, 1893. Serial No. 472,217. (No model.)

T0 on whom it may concern.-

Be it known that we, WILLIAM A. JOHN- New York, have invented certain new and useful Improvements in Pendent Incandescent Electric Lights, of which the following is a specification. Our invention relates to improved means, as hereinafter claimed, for suspending incandescent electric lights in such manner as to admit of their being readily adjusted horizontally and vertically relatively to fixed supports.

In the accompanying drawings, Figure 1 is a view in elevation on a scale much smaller than that of the remaining figures. Fig. 2is a central vertical section, the lamp and a portion of its suspending tube being omitted. Fig. 3 is a view with the lamp suspending tube in section on the line 3 of Fig.2, the parts above the line of section being viewed from below. Fig. 4 is a view mainly in vertical central section, showing certain details of construction.

A support A, which is adapted to be fixed to a ceiling, bracket, &c., in suitable way, as

by screws passing through the holes a, is made hollow and of approximately hemispherical form.

The upper section B of a lamp suspending tube has universally jointed frictional connection with thefixed support in the following way: A hearing piece 0 socketed within the fixed support is connected with the suspending tube section B. A socketD embracing the fixed support is carried by and adjustable on the tube section'B the lower end of which is threaded and engaged by a threaded adjusting sleeve E which serves also as a coupling to connect the upper tube section with another section F of the lamp suspending tube. To adapt the socketD to be yieldingly clamped about the fixed support so as to offer frictional resistance to the movement of the socket about the support, the socket is provided with slots 61 thus dividing it into a number of yielding or springy arms extending fromits edge or top inward or downward a suitable distance toward its center. From the above description it will be seen that by adj usting the sleeveE the fixed support maybe yieldingly clamped between its socket D and the bearing piece 0. In adjusting the sleeve the tube section B maybe held against turning by a suitable instrument inserted through one of the slots of the socket and engaging a hole bin the tube section. 'An additionalor lower section G of the suspending tube is adapted to telescope within the intermediate section F of the tube, and the lamp socketH of an ordinary incandescent electric lamp,

provided with a shade it, has universallyjointed connection with the lower section of the suspending tube in order that in whatever position the lamp may be swung it will depend -vertically from its suspending tube.

sistance to the movement of the lower section of the tube to guard against its sliding accidentally in the tube section F. At its upper end the lower or sliding section Gof the suspending tube is provided with a short lateral tubular guide or projection N which passes througha longitudinal slot 0 in the tube section F and serves to prevent turning of the sliding section independently of the section with which it connects. The wires conveying the current to and from the lamp pass through the lower section of the tube, out through the lateral extension at its upper end,

where a loop is formed to provide a sufficient length of wire to admit of the elongation of the tube to its fullest extent by the downward movement of its lower section; then into the tube section F by Way of opening f (which as well as the lateraltubular extension N may be hushed with some non-conducting mate- It will be seen that by com- I rial) and by way of the tube sections F and B to the fixed support, through the opening 9 of which the wires pass to any suitable safety catch or fuse box.

It will be seen that the lamp may be swung into any required position (two positions beside the Vertical are indicated by dotted lines Fig. 1), to direct the rays of light as desired; that it is held against accidental change of position by the frictional universal joint connection of the suspending tube with the fixed support, and that the lamp can be vertically adjusted by means of the telescoping suspending tube and be automatically held in the position of adjustment.

Our improvements may be modified in some respects without departing from the leading features of the invention; as by substituting a thin corrugated socket for the slotted socket D shown; or slotting or corrugating the bearing piece 0 instead of the socket D; and instead of locating the guide projection at the top of the sliding tube and passing the conducting wires by way of it through the slot in the tube section F, an equivalent projection maybe provided and the wires pass out directly from the end of the sliding tube instead of by way of the projection as we prefer.

\Ve claim as our invention 1. The combination of the support adapted to be fixed in position, the swinging suspending tube, the bearing piece within the support and connected with the suspending tube, the socket embracing the support, and carried by and adjustable on said tube, the adjusting sleeve on the suspending tube for yieldingly clamping the support between its socket and the bearing piece, the lamp carried by the suspending tube, and the con ducting wires passing through the support and tube, substantially as and for the purpose set forth.

2. The combination of the support, the suspending tube connected therewith and having the longitudinally slotted section,and the section sliding therein, and provided with the guide projection working in the slot of the slotted section the lamp at the lower end of said sliding section, and the conducting wires passing through the support and tube sections and extending outside the tube by way of the slot in one of its sections, substantially as and for the purpose set forth.

In testimony whereof we have hereunto subscribed our names.

WVILLIAM A. JOHNSTON. JOHN G. DAVIDSON. Witnesses:

SEYMOUR CASE, IRVING W. DECKER. 

